Process and apparatus for the continuous tension-free fixing and shrinking of cables of uncrimped filaments

ABSTRACT

PROCESS FOR THE CONTINUOUS, TENSION-FREE FIXING AND SHRINKING OF CABLE OF UNCRIMPED FILAMENTS, YARNS OR THE LIKE WHEREIN THE CABLE IS CONDUCTED BY MEANS OF A COMPRESSIBLE MEDIUM IN COILED OR SPIRAL FORM THROUGH A TUBULAR TREATMENT ZONE, AND DURING THE PASSAGE THROUGH THE SAID ZONE IS SUBJECTED TO FIXING AND SHRINKING TREATMENT; AND APPARATUS THEREFOR EMBODYING A VERTICAL TUBE AND A ROTATING, CABLE INJECTOR ON THE UPPER END OF THE TUBE, THE OUTLET OPENING OF WHICH TUBE LIES ECCENTRICALLY IN RESPECT TO THE AXIS OF ROTATION OF THE INJECTOR.

Sept. 21, 1971 5,0 N E ETAL 3,606,655

PRQCESS AND APPARATUS FOR THE CONTINUOUS TENSION-FREE FIXING AND SHRINKING OF CABLES OF UNCRIMPED FILAMENTS Filed Sept. 22, 1969 2 Sheets-Sheet 1 FIG! INVEN'TO RS SIEG FRIED OBERLANDER KARL OSTERTAG,

(1., K AZIQZA AM IFTORNEYS Sept. 21, 1971 5,0BERLANDER ETAL 3,606,655

PROCESS AND APPARATUS FOR THE CONTINUOUS TENSION-FREE FIXING AND SHRINKING 0F CABLES 0F UNCRIMPED FILAMENTS Filed Sept. 22, 1969 2 Sheets-Sheet I li b \9 FIG.3

0 m 0 Y I I I I I INVENTORS SIEGFRIED OBERLANDER KARL o TERTAG ATTORNEYS United States Patent PROCESS AND APPARATUS FOR THE CONTINU- OUS TENSION-FREE FIXING AND SHRINKING OF CABLES 0F UNCRIMPED FILAMENTS Siegfried Oberlander, Kolpingstr. 4,'Erlenbach am Main,

Germany, and Karl Ostertag, Rosenstr. 18, Elsenfeld am Main, Germany Filed Sept. 22, 1969, Ser. No. 859,957 Claims priority, application Germany, Oct. 9, 1968, P 18 01 976.6 Int. Cl. D02g 1/16; D06c 1/00 U.S. C]. 2859 Claims ABSTRACT OF THE DISCLOSURE Process for the continuous, tension-free fixing and shrinking of cable of uncrimped filaments, yarns or the like wherein the cable is conducted by means of a compressible medium in coiled or spiral form through a tubular treatment zone, and during the passage through the said zone is subjected to a fixing and shrinking treatment; and apparatus therefor embodying a vertical tube and a rotating, cable injector on the upper end of the tube, the outlet opening of which tube lies eccentrically in respect to the axis of rotation of the injector.

Processes are already known in which filaments or yarns, for the purpose of a thermal treatment, are deposited without tension or under a low tension in loop form in a tube and, by reason of the weight of the following filament or yarn or by reason of an external force applied thereto, are pressed through this tube.

Thus, in British Pat. 917,963, there is described a process in which yarn under slight tension or without tension is continuously subjected to a heat treatment, as it is deposited under the influence of its own weight in loops or convolutions in a straight, vertically standing tube. They are thermally treated therein and are drawn olf at an angle to the axis of this tube at a constant speed. The feeding of the yarn can take place with the aid of a pneumatically operated injector.

According to this British patent there is meant by yarn both individual threads and also thread cables or thread bands. The yarns can be supplied to the tube in crimped or uncrimped state.

Such an apparatus, in which the yarn is deposited by means of an injector at random in loops or convolutions in a straight, vertically standing tube, operates satisfactorily only as long as the denier of the yarn is not too great and the yarn is deposited in the tube in a dry state. Attempts to feed uncrimped yarn cables to an apparatus such as is described in the British patent in a moist state, however, have failed, because such moist cables have a certain stiffnessand cannot be deposited satisfactorily in the tube with an injector positioned concentrically with the tube axis. Furthermore, in the known apparatus there exists the danger that, through catching or entrainment of subsequent yarn loops, knots will form.

In German Pat. 805,415 a single thread or yarn is deposited continuously in loop form in a stuffing box passage with rectangular cross section for the purpose of thermal aftertreatment, and in the process is pressed through this passage by two pressure shutters going up and down on the thread or yarn entry side of the passage. This apparatus, too, in which the thread or yarn is wound about two arms oifset from one another by 180 and is thereupon deposited in oval loops, is unsatisfactory for the continuous treatment in particular of moist cables of uncrimped yarns or threads, because of the stiffness of this cable and the danger of knotting as a consequence of an unorderly depositing of the cable in the passage.

3,606,655 Patented Sept. 21, 1971 Ice Underlying the present invention is the problem of continuously fixing and shrinking without tension, cables of uncrimped threads or yarns whereby it is possible to subject moist and consequently stiff cables continuously to a thermal treatment in an operation wherein the feeding in and the drawing oif of the cable proceed without trouble, and the staying time of the thread cable in the treatment zone is precisely adjustable.

By cable there is meant a chemical spun cable as defined in German standard DIN 60 001 (September 1964) under point 2. The process of the invention and the apparatus of the invention, accordingly, can be used for chemical polymer endless yarns of technical denier up to more than 20,000 den.-=2.2 ktex.

In such technical endless yarns a continuous shrinking has hitherto been achieved by the means that yarn emerging from the steam chamber has been supplied to a further steam bath, namely the fixing chamber. There, the speeds of the stretching godet assemblies before and after the fixing chamber have been adapted to the desired degree of shrinkage. From the necessity that the yarn pasing between the lower part of the chamber and the upper part of the chamber must not be allowed to sag, the yarn was under tension during the shrinking and fixing process.

In the quest for a technical solution for the continuous, but tension-free shrinking and fixing treatment of uncrimped yarn cables, which are present in a moist stage after the stretching in the steam chamberas has already been explained for the state of technologythe known processes have not proved suitable, because of the stiffness present in such cables.

Surprisingly, it has proved that even such stiif cables can be deposited in an ordered state in a tube if they are fed from the stretching mechanism directly to a rotating injector which is rotatably driven by a suitable drive (friction wheel, belt or the like) and are discharged therefrom through an outlet situated eccentrically in respect to the axis of rotation and deposited in coil form in a tube.

The process of the invention for the continuous, tension-free fixing and shrinking of cables of uncrimped threads or yarns is characterized in that the cable is conducted by means of a compressible medium spirally through a tubular treatment zone, supplied to a winding device and during the passage through the treatment zone is subjected to a fixing and shrinking treatment.

The regulation of the staying time of the cable inside the treatment zone can be carried out by regulation of cable feed and draw-oft speeds to change the length of the coiled cable in the treatment zone or by increasing the friction between the coiled cable and the cylindrical wall of the treatment zone.

The staying time can be more simply regulated, however, if the cable is (1) supplied *by means of a compressible medium to a tubular treatment zone, (2) deposited in it spirally, (3) pressed through the treatment zone compressed in a tight coil by the weight of the subsequently fed and coiled cable, (4) drawn off from the treatment zone and (5) supplied to a winding device. The thread cable during the passage through the treatment zone is subjected to the fixing and shrinking treatment.

As compressible medium there can be supplied to the injector any gas which is not detrimental with respect to the particular cable. Preferably, the injector is driven by air. Care is to be taken that the compressible medium is removed from the cable after leaving the injector nozzle, so that no parts of the cable will be carried along by the turbulence of the flow to cause an undesired disorder in the coil windings.

In the execution of the process of the invention it has proved surprisingly that the residual shrinkage values which set in after the shrinking and fixing treatment under otherwise the same conditions lie lower than in the case of the processes practiced hitherto, in which shrinking and fixing are carried out under tension in a second steam chamber.

The apparatus of the invention for the continuous tension-free fixing and shrinking of cables of uncrimped yarns or threads is characterized by a vertical tube, open at the bottom, and an injector positioned at the upper end of the tube and rotatably driven in a known manner. The cable outlet opening is eccentric with respect to the axis of rotation of the injector.

In order to achieve a relatively tight coiling of the cable spiral in the tube and thereby be better able to regulate the residence time therein, the bottom end of the vertical tube is preferably arcuately bent laterally.

The bend of the lower end of the tube does not in itself need to be severe. A small angle of bending is sufficient if the tube is long enough so that frictional forces between the tubes cylindrical inner wall and the cable coil are sufiicient to provide a relatively tight or compact coiling.

The bending angle between the axis of the discharge end and the axis of the feed end of the tube is, however, preferably greater than 90, in order effectively to assure the relatively compact coiling and to make the tube length long enough to provide the desired residence time.

Although it is not necessary per se that the axis of the cable outlet opening of the injector be directed obliquely downward toward the inside wall of the tube, since the cable is thrust obliquely downwardly by centrifugal and gravitational force components on emergence from the outlet opening, the outlet opening directed obliquely downwardly toward the inside wall of the tube is preferred. With this construction, any drawing of the cable over a sharp edge is prevented.

The cross section area of the tube enclosing the cable treatment zone can theoretically be of arbitrary size and of arbitrary form, since the cable leaving the orbiting, eccentric cable outlet opening deposits itself in a horizontal laterally unbounded layer at the top of the coiled cables cylindrical column. In order, however, to prevent the outset disturbances in the cable column and troubles possibly arising therefrom, the tube has preferably a circular cross section area which is smaller than the cross section area of the respective coils of said cable column if said coils were deposited on a fiat, laterally unbounded plane by the rotating injector.

DESCRIPTION OF THE DRAWING The invention is explained in detail with the aid of the preferred embodiment illustrated in the drawing, wherein:

FIG. 1 is a side elevation, partly in vertical section, the preferred embodiment of the invention;

FIG. 2 is a vertical section of the rotating injector of FIG. 1; and

FIG. 3 is a v-n diagram with velocity of cable feed and rate of revolution of the injector as the ordinates and various theoretical cable coil diameters plotted thereon.

The cable 3, coming from a stretching mechanism (not shown), is supplied in the direction of the vertical arrow to the injector 1. The injector is supplied by the tube 2 with a compressible medium flowing the direction of a horizontal arrow 14. The injector 1 is rotated in a known manner, for example by a belt and pulley 5. The cable 3 and compressible medium are conveyed according to the invention through the eccentrically located cable discharge passage 23 to the eccentric, orbiting, discharge opening 4, preferably one directed obliquely downwardly toward the inside wall of the tube 6. There the compressible medium (e.g., air) can escape through openings 7 in the direction of the arrows from the tube 6, to avoid disturbances caused by gas turbulence in the longitudinally tightly coiled cable column 3a as a result of excessively high gas velocities in the tube 6. The cable 3 assumes a spirally downward path in the upper part of the tube 6 until it is laid on the upper end of the coiled column 3a, the layers of which become more and more longitudinally compacted. In consequence of its own weight or of the Weight of the cable subsequently laid thereon, the coiled cable column is conducted through a heating zone 8, the temperature of which sufiices to bring about the shrinking and fixing process.

The axis of the lower discharge end 6b of tube 6 forms with the axis of the vertical segment of tube 6 an angle a, which is designated as bending angle and, in the example represented, is greater than The fixed, shrunken cable is compressed in the bend 6a of the tube 6.

In the device represented, the tubular discharge end is a part of the tube 6. It is, of course, also possible to use a tubular discharge end 612 which can be placed removably on the tube 6. When an alteration is desired, it can be interchanged with another end 6b to alter the bending angle a.

The fixed and shrunken cable is drawn off in the direction of arrow 9, i.e., in outlet direction of the tube end 6b. Because of the untangled coiling, the cable can be drawn off without diificulty and be supplied over deflection bars to a winding device (not shown).

If desired, a regulating device can provide for a uniform staying time or a uniform degree of filling. It is possible, for example, to have a photoelectric cell (not shown) above the heating zone monitor the height of coiled column 3a and to control the draw-off speed in response to the height level.

The diameter of the turns can be adapted in the case of different cable thicknesses to the frictional relations in the tube 6 by altering the injector turning rate, the feed velocity of the cable, e.g., by a pair of feed rollers above the injector, and the velocity of the compressible medium, e.g., through a choke valve on the tube 2. Thereby there is always assured an orderly coiling of the cable and its trouble-free draw-Off.

The injector is illustrated in detail in FIG. 2. It comprises a hollow stationary head 10 having an axially extending cable passage tube 11 mounted therein with a wear-resistant liner 12 at the mouth 13 into which the cable 3 is fed in the direction of the arrow 15.

The injector rotor is rotatably supported in the stationary head 10 by the ball bearing 27, the outer race of which is supported on the stationary head by the ring 17 and the inner race of which is supported on the rotating member by the ring 18. The rotor 16 is rotated by the belt and pulley drive 5.

Air or other compressible medium is fed by the tube 2 and the passge 19 into the cylindrical space 20 surrounding the tube 11. It flows downwardly through the cylindrical passage 21 in the rotor 16 and thence into a constricted throat 22 surrounding the lower end of the cable feed tube 11. The air flowing through the throat passes into the curved passage 23 in the lower end of the rotor 16 and draws the cable therewith through the feed tube 11. The cable is thus fed in a spiral path as shown in FIG. 1 into the vertical tube 6. The air or other compressible medium is discharged through the openings 7 in the upper portion of the vertical tube 6, and the cable 3 is laid in the longitudinally tight coil 3a in the lower portion of the vertical tube 6 below the openings 7, in which form it is subjected to the heat fixing treatment provided by the heated jacket 24 surrounding the lower portion of the tube 6. A heating medium, such as steam or other heating vapor or a heated liquid, is supplied to the jacket 24 through heating medium supply and discharge tubes 25 and 26.

Although the velocity of the compressible medium can vary within wide limits, it is preferably to be chosen of such a magnitude that the cable does not become slack as it is fed to the injector 1.

By prescription of the thread entry velocity at the inlet pair and of the speed of rotation of the rotary injector nozzle, one can determine a theoretical spiral winding diameter d Taking the longitudinally tightly coiled cable column 3a in the tube 6, the spirals have a pitch which corresponds to the cable thickness. This pitch, however, is negligible for the determination of the theoretical winding (spiral) diameter of the coil so that as a basis for calculation exactly the circular circumference of the coils can be used.

If there is designated the input velocity v in meters per minute of the cable into the injector, and with the injector rotating at n r.p.m., then, with ,u=1r-d =v/n[m] there is yielded the theoretical coil spiral diameter at If there are substituted d in cm., v in m./min. and n in r.p.m., then there holds the relation If v is plotted against 12 (v-n diagram, FIG. 3), then there is obtained for d straight lineplottings. From the v-n diagram there can then be determined the most favorable operating conditions for the process of the invention.

If the input velocity can be well kept constant and crude fluctuations of the spiral diameter are to be avoided, it is expedient to work in the range of high rotational speeds, from about n=1500 r.p.m. upward, since at these rates rotational speed fluctuations have negligible effect On d t When the cable thickness and the required staying times permit, the smaller theoretical coil winding diameter is to be preferred over a greater diameter since a lower diameter fluctuation can be achieved.

Experiments have shown that with a bending angle a: 120 and polished steel tube 6, 6a and 6b, the actual winding diameter differs from the theoretical by about The deviation is attributed to the stiffness of the yarn cable. Because of the bending tension of the cable, the windings have a tendency to increase in diameter. They are hampered in this, however, in part by the windings lying above or underneath.

EXAMPLE In a tube according to FIG. 1 (inside tube diameter 40 mm., length of the cylindrical part 500 mm.) a thread cable d 940 f. 140 of unstabilized, heat-resistant nylon 6,6ad-ipic acid-hexamethylene diamine polyamide (strength 63.8 Rkm.; extension 15.2%; boiling shrinkage 6.7%) is shrunk and fixed without tension. The input velocity amounts to 200 m./min.; the draw-off speed fluctuates in dependence on the control between 185 m./min. and 210 m./min. The mean staying time amounts to 3 min. 40 sec.

Depending on the fixing temperature there are yielded the following properties of the cable leaving the tube:

' tern erature de rees 180 190 Flxmg p g 64.3 68.9 21.0 19.1

Comparative test lIn a comparative test a thread cable dtex 940 f. 140 of unstabilized, heat-resistant nylon 6.6 (strength 63.8 Rkm.;

Fixing temperature, C. 180 Strength, Rkm 70. 9 68. 2 Extension, pereenL. 19. 2 18. 0 Boiling shrinkage, percent 4. 5 4. 4

From the comparison it is perceived that the longer staying times possible in the fixing tube as well as the tension-free residence in the fixing zone at the same temperatures and at equal input velocities lead in the case of the invention to considerably less boiling shrinkage. Also the extension is increased by use of the process of the invention.

The favorable results achieved through the invention can be further improved by increase of the residence time, for example, by lengthening the fixing zone.

In summary, the invention provides a process for the continuous tension-free fixing and shrinking of cables of uncrimped yarns by feeding by a compressible medium, e.g., air, a cable of uncrimped yarns into a vertical tubular fixing and shrinking zone while rotating the cable to cause it to feed into said zone in a spiral path. It forms a longitudinally tight coil and passes through the zone in this form while being subjected to an elevated temperature fixing treatment, e.g., 150-220 C. The cable coil may be conveyed through the zone by its own weight, and preferably is discharged from the tubular zone by drawing it off from a tubular discharge end at an oblique angle to the vertical tubular zone.

The apparatus for the continuous tension-free fixing and shrinking of yarn cables comprises a vertical tube, a rotating cable injector at the upper end of said tube for feeding cable into said tube in a spiral path and forming in said tube a longitudinally tight coil of said cable, and a tubular discharge member at the lower end of said vertical tube with its longitudinal axis oblique with respect to the vertical axis of said vertical tube. The tubular discharge member is connected with said lower end of said vertical tube by a tubular bend with the axis of said discharge member extending obliquely upwardly. The axis preferably always is at an angle to the vertical axis of said vertical tube. The injector has a rotor with a centrally axial cable passage extending therethrough with the lower end of said passage directed obliquely downwardly toward the inside wall of said vertical tube.

Preferably, the circular cross section of said vertical tube is smaller than the cross section of the coiled, cylindical cable column if the latter were deposited in a flat laterally unbounded horizontal layer by said rotating injector. The cable is conveyed into the vertical tube by injecting a stream of compressible medium into the cable passage through said rotating injector to feed said cable in a tension-free state through said injector and into said vertical tube. There are passages through the upper portion of said vertical tube for flow of the compressible medium out of the upper portion of said tube, and a heating jacket or the like is provided on the lower portion of said vertical tube for heating said lower portion to an elevated fixing temperature.

It is thought that the invention and its numerous attendant advantages will be fully understood from the following description, and it is obvious that numerous changes may be made in the form, construction and arrangement of the several parts without departing from the spirit or scope of the invention, or sacrificing any of its attendant advantages, the forms herein disclosed being preferred embodiments for the purpose of illustrating the invention.

The invention is hereby claimed as follows:

1. A process for the continuous tension-free-fixing and shrinking of cables of uncrimped yarns of adipic acidhexamethylene diamine polyamide which comprises feeding in a rotating spiral coil by means of compressed air a moist cable of uncrimped yarns of adipic acid-hexamethylene dialnine polyamide into a tubular fixing and shrinking zone of uniform diameter and having a vertical axis in the form of a helical coil of said cable, said tubular zone having a diameter smaller than the diameter of the respective rotating spiral coils of said cable if said coils were deposited in a fiat, laterally unbounded, horizontal layer, passing said cable in a longitudinally tightly coiled helix through said zone by the accumulated weight of the coil of said cable at a rate to provide the desired residence time therein, and therein subjecting said cable to an elevated temperature fixing treatment.

2. A process as claimed in claim 1, wherein said tubular treatment zone includes a tubular bend and a tubular discharge end at an oblique angle to said vertical axis.

3. Apparatus for the continuous tension-free fixing and shrinking of yarn cables which comprises a vertical tube of uniform diameter, a rotating cable injector at the upper end of said tube for feeding cable into said tube in a spiral path and forming in said tube a longitudinally tight coil of said cable, said injector having a rotor with centrally axial cable passage extending therethrough, the lower end of said passage directed obliquely downwardly toward the inside Wall of said vertical tube, means for injecting a stream of compressible medium into the cable passage through said rotating injector to feed said cable in a tension-free state through said injector and into said vertical tube, a tubular discharge rnember at the lower end of said vertical tube with its longitudinal axis oblique with respect to the vertical axis of said vertical tube, and pas- References Cited UNITED STATES PATENTS 2,947,595 8/1960 Moelter 264168 2,971,243 2/1961 Burns 2872.l2 2,971,683 2/1961 Paulsen 2872.l2 3,000,060 9/1961 Shattuck et al. 281.6 3,114,958 12/1963 Parek et al. 28l.6 3,166,820 1/1965 Taul et al. 28-l.6 3,343,240 9/1967 Parmeggiani et al. 28-72.14 3,353,240 11/1967 Hodges et al. 28--72.14 3,423,266 1/1969 Davies et a1 2872.l2 3,438,101 4/1969 Le Noir et al 264l68 3,444,600 5/1969 Scragg et al 2872.l4 3,217,482 11/1965 Baer 281.3 3,303,546 2/1967 Van Blerk 281.3 3,409,956 Ill/1968 (Longbottom et al. 2872.l1

JAY H. WOO, Primary Examiner US. Cl. X.R. 

